product_list = [
    (‘MacBook‘, 9000),
    (‘kindle‘, 500),
    (‘tesla‘, 900000),
    (‘book‘, 100),
    (‘bike‘, 2000),
]

saving = input("please input your money:")
shopping_car = []

if saving.isdigit():
    saving = int(saving)

    while True:
        #打印商品內容
        for i, v in enumerate(product_list, 1):
            
 
print(i, ">>>", v)

        #引導用戶選擇商品
        choice = input("choose goods that you want to buy[exit:q]:")

        #驗證輸入是否合法
        if choice.isdigit():
            choice = int(choice)
            if choice > 0 and choice <= len(product_list):

                #將用戶選擇商品通過choice選出
                p_item = product_list[choice - 1]

                
 
#如果錢足夠，用saving減去商品價格，並將該商品加入購物車
                if p_item[1] <= saving:
                    saving -= p_item[1]
                    shopping_car.append(p_item)

                else:
                    print("-----------------")
                    print("Sorry, your balance is not enough.")
                    
 
print("Your balance: " + str(saving))
                    print("-----------------")
                    continue
                print("-----------------")
                print("You have chose " + p_item[0])
                print("Your balance: " + str(saving))
                print("-----------------")
            else:
                print("Non existent")
        elif choice == ‘q‘:
            print("---------------")
            print("You have chose the following goods:")
            print("Goods\t\tnumber\tPrice")

            num = 1
            #循環遍歷購物車裏面的商品，購物車存放的是已買商品
            for i in shopping_car:
                print(i[0] + "\t\t" + str(num) + "\t\t" + str(i[1]))
            print()
            print("balance :", saving)
            print("---------------")
            break

        else:
            print("invalid input")

Python小代碼_3_購物車